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This work focuses on an improved method that enables us to measurein situGaN film photoluminescence (PL) under Ar or N2plasma etching. Although the background signal is large and increases with bias voltage, the GaN PL can be obtained after subtraction of this background from the total luminescence. Moreover, after plasma etching, the intensities of the near-band-edge and the yellow luminescence decrease significantly. It is suggested that this behaviour is strongly related to the heavy plasma-induced damage, which includes non-radiative defects and deep-level defects, such as Ga vacancies and/or C impurities. [ABSTRACT FROM AUTHOR]

Abstract: We report on a unique delaminating morphology involved a transition from straight-sided to telephone cord buckles in SiAlNx films sputtered on 6-mm thick glass substrates. It is found that the straight-sided buckle tip propagates forward with an almost uniform speed. Usually, the straight-sided buckle is unstable, and it can evolve into the telephone cord buckle gradually accompanying with the enlargement of the buckle width. The structural characteristics and dynamical behaviors of the unique delaminating morphology have been investigated in detail. The physical mechanism of the transition behavior is analyzed based on the stability diagram of unilateral buckling patterns. [Copyright &y& Elsevier]

Silver (Ag) films have been deposited on rough substrates (including frosted glass and silicone grease), and for comparison on flat glass, by DC-magnetron sputtering, and their sheet resistances measuredin situduring deposition. It is found that the growth of Ag films proceeds through three distinct stages: discontinuous, semi-continuous, and continuous regimes. The sheet resistance on rough substrates jumps in the vicinity of the percolation threshold, whereas the resistance on flat substrates decreases monotonically during deposition. The abnormalin situelectric properties on rough substrates are well explained based on the differences of the growth mechanism and microstructure of Ag films on different substrates. [ABSTRACT FROM AUTHOR]

We have developed a method that enables us to in situ observe full photoluminescence (PL) spectra of n-type GaN film under plasma conditions. By subtracting background plasma noise from the total one, respectable luminescence of GaN film can be successfully obtained. After the plasma exposure, the near-band-edge emissions and yellow luminescence decrease but the blue luminescence intensity increases mainly due to the top surface damage of the GaN film. The results give us evidence that this in situ PL probe method can be potentially used for real-time damage monitoring of GaN film surfaces in plasma processes. [ABSTRACT FROM AUTHOR]

Abstract: We report on the morphological selections and dynamical evolutions of buckling patterns in annealed SiAlN x films deposited on 6mm thick glass substrates. Various buckle modes, including straight-sided, bubble (or varicose) and telephone cord structures, are found to coexist in the same sample. The straight-sided mode appears only when the buckle width is less than a critical value (about 50μm in the experiment). When the buckle width increases, the straight-sided buckle destabilizes and evolves into the telephone cord structure gradually. If the buckling patterns form ridge cracks, the original straight-sided blisters and telephone cord buckles with smaller widths invariably evolve into the bubble mode, whereas the telephone cord buckles with larger widths can keep the antisymmetric mode. These buckle modes and their dynamical evolutions are discussed based on the stability diagram of unilateral buckling patterns. [Copyright &y& Elsevier]

Abstract: We report on the coalescence behaviors of telephone cord (TC) buckles in SiAlNx films sputtered on 6mm thick glass substrates. The buckles are found to propagate from the film edges to the central regions gradually after the sample was annealed at 700°C for 4.5min and then cooled to ambient temperature. If two buckles meet on their ways during propagation, they may coalesce into one buckle. The buckle morphology after coalescence is strongly dependent on the coincided degree and the phase difference of the original buckles. The coalescence processes and morphological characteristics of the TC buckles with diverse coincided degrees and phase differences have been investigated in detail. [Copyright &y& Elsevier]